The present invention relates to a gasket and a fuel cell.
As described in Japanese Laid-Open Patent Publication No. 2008-21636, a fuel cell adapted to be installed in a vehicle includes an end plate, which is arranged at an end of a cell stack in the cell stacking direction, and a case covering the periphery of the cell stack. A gasket, which maintains airtightness of the interior of the case, is arranged between the end plate and the case. The gasket is configured to seal the gap between the end plate and the gasket and the gap between the case and the gasket. By sealing these gaps, the gasket maintains airtightness of the interior of the case. The end plate of the fuel cell is manufactured using aluminum to decrease the weight of the end plate by a die casting method, which is a highly productive casting method.
However, despite the gasket arranged between the end plate and the case as described in the publication, fluid such as water may enter the gap between the opposed surfaces of the end plate and the case, which clamp the gasket, from the exterior of the case, to the point at which sealing by the gasket is effectuated with respect to the end plate and to the point at which sealing by the gasket is effectuated with respect to the case.
If the fluid that has entered the gap is salt water, the salt water may cause corrosion in the end plate, which is made of aluminum, in the vicinity of a point (hereinafter, referred to as a sealing point) at which sealing by the gasket is effectuated. Such corrosion in the vicinity of the sealing point decreases sealing performance of the gasket with respect to the end plate, thus hampering maintenance of the airtightness of the interior of the case.